Amazon's largest outdoor drone testing site is a field somewhere in the UK — but it won't say where

Amazon's largest drone delivery test site is a secret site somewhere in the UK, according to the cofounder of Amazon's Prime Air business.

Daniel Buchmueller, who leads Amazon's drone development operations in the UK, made the announcement at the Amazon Web Services Summit in London on Thursday.

"We have [drone] development centres right here in the UK. In the United States, in Austria, and in Israel," he said.

"These are places where we have dedicated indoor facilities. But we also have outdoor testing facilities. In fact, our largest outdoor facility is right here in the UK."

Several Business Insider sources have suggested that the outdoor site is somewhere in Cambridge, which would make sense as Amazon has an R&D facility in the city.

Business Insider asked Amazon about the Cambridge site. We requested the address, the size, and we also asked how often Amazon uses it.

An Amazon spokeswoman replied: "I did not say our outdoor facility was in Cambridge; just in the UK. As I'm sure you can appreciate, we do not disclose the other details you requested."

The fact that Amazon is refusing to say where its UK drone testing site isn't that surprising. It probably doesn't want people turning up there and capturing Amazon's drone activities with their smartphones. Tests don't always go to plan and a viral video of an Amazon drone crashing into a tree wouldn't help Amazon to get the drones approved and into operation.

Buchmueller said that Amazon has over a dozen prototype drones in operation worldwide. That figure may seem relatively low but it's still early days for Amazon Prime Air.

Amazon wants to use the drones to deliver packages to people's homes and offices in under 30 minutes. It claims they will be greener, cheaper, and safer than the vans that are currently used to deliver Amazon packagers.

The battery-powered vehicles rise vertically like a helicopter up to 400 feet before flying up to 15 miles at speeds of up to 50mph. The 25kg drones are "highly automated," according to Buchmueller, who added that they have been designed to carry packages up to 2kg in weight.

Speaking at the same event, Liam Maxwell, the government's chief technology officer, said the UK is "open" and "more progressive" than other countries when it comes to drone testing.